package com.li.interceptor;

import com.google.gson.Gson;
import com.li.constant.BaseContext;
import com.li.pojo.po.Result;
import com.li.properties.JwtProperties;
import com.li.utile.JwtUtil;
import io.jsonwebtoken.Claims;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * jwt令牌校验的拦截器
 */
@Component
@Slf4j
public class JwtTokenInterceptor implements HandlerInterceptor {

    @Autowired
    private JwtProperties jwtProperties;
    /**
     * 校验jwt
     *
     * @param request
     * @param response
     * @param handler
     * @return
     * @throws Exception
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        //判断当前拦截到的是Controller的方法还是其他资源
        if (!(handler instanceof HandlerMethod)) {
            //当前拦截到的不是动态方法，直接放行
            return true;
        }
        //1、从请求头中获取令牌
        String cookie = request.getHeader("Cookie");
        int i = cookie.lastIndexOf("=");
        String token = cookie.substring(i + 1);

        //2、校验令牌
        try {
                log.info("jwt校验:{}", token);
                Claims claims = JwtUtil.parseJWT(jwtProperties.getSecretKey(), token);
                String name = claims.get("name").toString();
                log.info("当前后台员工名称：{}", name);
                //添加操作者Id到ThreadLoad
                BaseContext.setCurrentName(name);
                //3、通过，放行
                return true;
        } catch (Exception ex) {
            //4、不通过，响应401状态码
            log.info("jwt校验失败,{}",ex);
            Result result = new Result(401, "token校验失败", null);
            String json = new Gson().toJson(result);
            response.getWriter().println(json);
            return false;
        }
    }
}
